Evo Magazine's Review of the BMW Performance Suspension

[///M1]

Most of you know Evo magazine, a very credible UK car publication. Well, if you have been following the back pages over the last few months, the staffers took on a 135i as one of their long term fleet vehicles. They have made several mods month-over-month, starting with the wheels (opted for the BMW performance rims), which funny enough with tires only resulted in...1/2lb weight loss per corner (although the tires they were replacing were almost shot, so likely a lb or so lighter than when new).

They just installed the BMW Performance Suspension and have a quick 1/2 pager commentary. When they got the car, in fully stock form they recorded several laps (at Bedford Autodrome), along with an M3. Their quest is to build this car to eclipse the stock M3s time. So they installed the suspension, but very suprisingly their lap time had increased. They too were puzzled and couldn't attribute it to anything in particular (weather conditions in both tries were silimar). Stock time was 1:28.7 vs 1:29.4 with the BMW PS and wheels. Both new and old tires were RFTs, the new ones being Dunlop SP Sport 01 rather than the stock Bridgestones RE050As. The stock M3's time they are gunning to beat is 1:25.9

They are quite happy with the suspension per se, so the disappointing track time is not meant to bash it. In fact they said that, quote: "feels really good now, less fuzzy, more poised." They proceed to say the car felt more stable, decisive, biddable, mostly because of noticeably less roll.

So to conclude, staff wrote: "There are 2 certainties: After spending GBP 5,000 on wheels and suspension, we have done nothing to improve the car's lap time. But we have improved the feel of the car on road and on track, wheel control is better and the car drives more positively."

By next month they would have added the BMW Power Pack, so stay tuned.

[BMW86]

Good find. That's disappointing that the lap time did not increase. I'm tossing up between the Performance Suspension and the KW V1's. I'm not a track junkie but I have an aggressive driving style and both are similarly priced around the US $1k mark.

[ptack]

So far it seems that none of the BMW upgrades for the 135i do anything at all to significantly improve performance. I wonder if that's no accident. Can't wait to read about the engine upgrade.

[SlicktopTTZ]

Very disappointing. I want to eliminate understeer and roll but I have a 240sx with Tien coil-overs and it absolutely SUCKS on crappy roads. I don't want that to happen again. Are the KW's more or less harsh than BMW PS, and is it even an increase in performance?

[///M1]

I've been debating too between the BMW PS and the KWs. The good thing about the former is of course the warranty, and to me personally they would come at no cost as I have accumulated enough pts on my BMW credit card to redeem it for free. Is that enough to have me go for it? Probably not yet, I am still doing research and poling folks around.

If I go the KW way, it will be the Variant 3 with the external reservoirs. I have a very similar setup on my RS4 (suspension sold by Stasis - a very reputable Audi tuner, but shock absorbers are manufactured by Ohlin according to Stasis specs). They are simply wonderful, as I can can adjust the rebound through the canisters residing in the engine bay at an easy click, literally a 1 min job. Works great if you do track and street, as the adjustment takes no effort. But I fear the ride comfort on a smaller base car like the 135i will be greatly comprimised with coilovers...

[igom3]

Bummer I was looking to order it from Tisher BMW, but now I’m not so sure. Also I was looking to get Bilstein PSS10. What do you guy’s think of PSS10. Thanks

[BMW86]

Originally Posted by ///M1

If I go the KW way, it will be the Variant 3 with the external reservoirs. I have a very similar setup on my RS4 (suspension sold by Stasis - a very reputable Audi tuner, but shock absorbers are manufactured by Ohlin according to Stasis specs). They are simply wonderful, as I can can adjust the rebound through the canisters residing in the engine bay at an easy click, literally a 1 min job. Works great if you do track and street, as the adjustment takes no effort. But I fear the ride comfort on a smaller base car like the 135i will be greatly comprimised with coilovers...

Sorry for the newbie question but how do you make adjustments? I might possibly get the KW V2's. You mentioned that it's in your engine bay and it only takes a few clicks. I would have mine professionally installed but how would I be able to fine-tune my ride comfort myself? Where abouts in the engine bay?

[///M1]

Originally Posted by BMW86

Sorry for the newbie question but how do you make adjustments? I might possibly get the KW V2's. You mentioned that it's in your engine bay and it only takes a few clicks. I would have mine professionally installed but how would I be able to fine-tune my ride comfort myself? Where abouts in the engine bay?

Sorry if I confused you, I was talking about the Ohlins on my RS4 that have external canisters which reside in the engine bay and have a click wheel on top of each canister that controls the rebound and compression setting (can instantaneously make it firmer or stiffer). I think the KW V3s are on the same principle.

Some pics of my install and general info about them. If they made a set for the 135i I would be all over them!

http://www.vividracing.com/catalog/p...njn3l3r60rkgk4

[Dangerlucas]

FYI, I've got KW v3s on my car and the do not have external reservoirs. Pictures I've seen indicate that they do, but it's not the case for the 1 series suspension. That said I would still highly recommend them.

Although, if I had to do it again I would probably get them through HPautowerks and get some custom swift springs.

[///M1]

Originally Posted by Dangerlucas

FYI, I've got KW v3s on my car and the do not have external reservoirs. Pictures I've seen indicate that they do, but it's not the case for the 1 series suspension. That said I would still highly recommend them.

Although, if I had to do it again I would probably get them through HPautowerks and get some custom swift springs.

How is the ride quality relative to stock (say on a scale of 1-10 if 10 is stock)? I guess a lot depends where you drive, here on the East Coast (NYC area) roads are terrible, so I am very weary about putting coilovers on a short base car like the 1-.

[Alow]

Did they have the same tires before and after the suspension change? if not, its not an apples to apples comparison. Tires are one of the biggest factors in grip level. If the tires are 3 seconds slower, the results are skewed.

[bradford]

Originally Posted by ///M1

I've been debating too between the BMW PS and the KWs. The good thing about the former is of course the warranty, and to me personally they would come at no cost as I have accumulated enough pts on my BMW credit card to redeem it for free. Is that enough to have me go for it? Probably not yet, I am still doing research and poling folks around.

If I go the KW way, it will be the Variant 3 with the external reservoirs. I have a very similar setup on my RS4 (suspension sold by Stasis - a very reputable Audi tuner, but shock absorbers are manufactured by Ohlin according to Stasis specs). They are simply wonderful, as I can can adjust the rebound through the canisters residing in the engine bay at an easy click, literally a 1 min job. Works great if you do track and street, as the adjustment takes no effort. But I fear the ride comfort on a smaller base car like the 135i will be greatly comprimised with coilovers...

FYI, Turner has a Moton kit for the 135i. $4k though... :-/

Nice ride - I just came out of a B6 S4.

[///M1]

Originally Posted by Alow

Did they have the same tires before and after the suspension change? if not, its not an apples to apples comparison. Tires are one of the biggest factors in grip level. If the tires are 3 seconds slower, the results are skewed.

As I noted in the original post: "Both new and old tires were RFTs, the new ones being Dunlop SP Sport 01 rather than the stock Bridgestones RE050As."

So seems to me it was a fairly apples-to-apples comparo unles one can make the statement that Dunlop RFTs are much crappier than Bridgestones. I couldn't tell you, my Bridgestones didn't last 1K miles, hated them and replaced them with 'normal' UHP tires.

[syenisch]

I would be interested to see the comparison between the OEM M Sport suspension and the Performance Suspension on a nonRFT tire such as PS2s or Star Specs. I think it might tell a different story. The softer OEM M Sport suspension might be more suitable for the hard sidewalls of the RFTs. Perhaps adding stiffer suspension removes the "compliance" needed for the RFTs to work optimally. I suspect Performance Suspension on nonRFTs would outperform OEM M Sport suspension on nonRFTs. That is only my opinion though.

Edit: The RFTs already have notoriously stiff sidewalls. I believe the Performance Wheels are larger in diameter. Now you've got a shorter (and more importantly stiffer) sidewall than before with stiffer suspension and no better rubber. The weak link is the tires, and you've made them WORSE with the suspension and wheel change. I maintain my belief that if you put on better rubber the car with Performance Suspension and Wheels wins.

[///M1]

Originally Posted by syenisch

I would be interested to see the comparison between the OEM M Sport suspension and the Performance Suspension on a nonRFT tire such as PS2s or Star Specs. I think it might tell a different story. The softer OEM M Sport suspension might be more suitable for the hard sidewalls of the RFTs. Perhaps adding stiffer suspension removes the "compliance" needed for the RFTs to work optimally. I suspect Performance Suspension on nonRFTs would outperform OEM M Sport suspension on nonRFTs. That is only my opinion though.

Edit: The RFTs already have notoriously stiff sidewalls. I believe the Performance Wheels are larger in diameter. Now you've got a shorter (and more importantly stiffer) sidewall than before with stiffer suspension and no better rubber. The weak link is the tires, and you've made them WORSE with the suspension and wheel change. I maintain my belief that if you put on better rubber the car with Performance Suspension and Wheels wins.

Don't think Evo will keep the car long enough to go through this set of RFTs, and then switch to regular tires, but you never know. They have an e-mail box, so we can slide that recommendation

As far as the performance wheels, I believe they stayed with the 18 inch option, so neither the profile nor width of the tire has changed, and arguably the Dunlop and Bridgestones are close enough so that the increase in lap times cannot be explained by this alone (and weather was not a factor). You might be correct though that the RFTs are better suited for the stock sport suspension. Either way, you can't argue that after spending the equivalent of nearly $8K on new rubber, suspension and wheels they were left quite disappointed that not only they couldn't improve the stock lap times, but faired off worse...

[syenisch]

Originally Posted by ///M1

Don't think Evo will keep the car long enough to go through this set of RFTs, and then switch to regular tires, but you never know. They have an e-mail box, so we can slide that recommendation

As far as the performance wheels, I believe they stayed with the 18 inch option, so neither the profile nor width of the tire has changed, and arguably the Dunlop and Bridgestones are close enough so that the increase in lap times cannot be explained by this alone (and weather was not a factor). You might be correct though that the RFTs are better suited for the stock sport suspension. Either way, you can't argue that after spending the equivalent of nearly $8K on new rubber, suspension and wheels they were left quite disappointed that not only they couldn't improve the stock lap times, but faired off worse...

Ahh OK. Good info about the diameter and width of the Performance Wheels. As you said though, the Performance Wheels offered little if any weight savings, so you could consider that a purely cosmetic mod. Not performance gains should be expected there. The rubber was purely maintenance since they stayed with RFT's. No performance gains should be expected there either.

Glad you mentioned the weather wasn't a factor. I thought about that as well but neglected to mention it in my post.

I should note that I am not trying to be argumentative. I just feel this test only tells us that all other things being stock, the stock suspension outperforms the performance suspension on the track. I would venture to say that most of us who go with the performance suspension will end up changing to nonRFTs as well. Plus I am close to pulling the trigger on the performance suspension, so I have to defend it for the sake of my own sanity.

[///M1]

Originally Posted by syenisch

Ahh OK. Good info about the diameter and width of the Performance Wheels. As you said though, the Performance Wheels offered little if any weight savings, so you could consider that a purely cosmetic mod. Not performance gains should be expected there. The rubber was purely maintenance since they stayed with RFT's. No performance gains should be expected there either.

Glad you mentioned the weather wasn't a factor. I thought about that as well but neglected to mention it in my post.

I should note that I am not trying to be argumentative. I just feel this test only tells us that all other things being stock, the stock suspension outperforms the performance suspension on the track. I would venture to say that most of us who go with the performance suspension will end up changing to nonRFTs as well. Plus I am close to pulling the trigger on the performance suspension, so I have to defend it for the sake of my own sanity.

No worries, I don't think people took your posts as argumentative.

Def let us know how you fair off with the BMW PS + non-RFTs. The tires were the first thing I changed on the car (running General Exclaim 225/255s UHP tires), and def feeling the softer sidewall on shapr turns. The only negative to this swap IMO, otherwise car feels much better, especially in rain and cold, much quieter and ride comfort of course is significantly improved. Suspension is next on my ,od list after a mid-pipe and axel back are being installed in early Jan!

[brracing]

Just to add to this thread relative to getting a suspension that can improve handling, reduce understeer, and reduce track times....it is easily doable, and produce a car that is better than the M3.

We have drastically reduced our track times from when we started at "stock", and can easily toast any E46 M3 or current generation E90/E92 M3, so the goal can be accomplished. But, there is no simple and cheap fix that we found...it takes a bunch of steps, not just throwing new shocks and springs and struts at the car. It takes a thorough approach...but happy to demonstrate the results that can be achieved.
We have (just suspension pieces noted here) -
M3 front lower control arms
Vorshlag camber plates
AST 5300 remote resv front struts
Front Race springs - different spring rate
M3 rear control arms
M3 rear subframe bushings
AST 5300 remote resv rear shocks
Rear Race springs - different spring rate from stock
18" and 19" wheel sets, nearly symmetrical in size all around
Different alignment settings

Some other pieces that also have beneficial impact - weight savings done to our car

[Schnorbitz]

This thread is a waste of time, of course the anomaly in the lap times is attributable to the different tyres, Evo said it themselves. To assume that just because both types of tyres are RFTs there will be no difference in their relative performance is very naive indeed.

[Alow]

Originally Posted by Schnorbitz

This thread is a waste of time, of course the anomaly in the lap times is attributable to the different tyres, Evo said it themselves. To assume that just because both types of tyres are RFTs there will be no difference in their relative performance is very naive indeed.

+1

[bradford]

Originally Posted by brracing

We have (just suspension pieces noted here) -
M3 front lower control arms
Vorshlag camber plates
AST 5300 remote resv front struts
Front Race springs - different spring rate
M3 rear control arms
M3 rear subframe bushings
AST 5300 remote resv rear shocks
Rear Race springs - different spring rate from stock
18" and 19" wheel sets, nearly symmetrical in size all around
Different alignment settings

Stock 135i ARBs?

[///M1]

Originally Posted by Schnorbitz

This thread is a waste of time, of course the anomaly in the lap times is attributable to the different tyres, Evo said it themselves. To assume that just because both types of tyres are RFTs there will be no difference in their relative performance is very naive indeed.

If it is a waste of your time, then feel free to bypass it without making worthless commentary. All I was doing is sharing findings by a credible UK magazine most people in the US don't have access to.

Evo did not say what you are claiming, that the "anomaly in the lap times is attributable to the different tyres". What they did say was the following: "There is no stand-out area where the lap speed has changed, it's just a fraction here and there. It could be that the Dunlop Runflats are a fraction less good around the track than the original Bridgestones, perhaps because being newer their thread depth is deeper. Whatever, there are 2 certainties: After spending GBP 5,000 on wheels and suspension, we have done nothing to improve the car's lap time. But we have improved the feel of the car on road and on track, wheel control is better and the car drives more positively"

Look at the TireRack or other tire comparos, these tires are not far apart at all. Yes, I wish too they did an apples-to-apples comparo and kept the same brand tires (but then one could make a claim newer tires have better grip than older ones do, so it will never be an apples-to-apples comparo), but it is what it is. I think the takeaway is that the BMW PS definitely improves the feel and balance of the car. Is that great on the street - yes. Is it the optimal performance suspension for the track - clearly not. But most people here are looking for an upgrade to the ($hitty) stock suspension for a better EVERY DAY setup, compromising perhaps a tad of ride comfort but gaining better control and feel. If you are a track junkie, clearly the BMW PS is not right for you (nor is any suspension released by a car manufacturer for that matter), might as well go with coilvers if carving apexes and diminish lap times is what you are after.